ABSTRACT
Fungi play a pivotal role in the forest food web, are central to its functioning and essential to maintaining a healthy balance. They interact with the food chain at many levels. Mycorrhizal fungi live together with “the producers” in a mutualistic association on the roots of plants. Saprobic fungi are “decomposers” or “recyclers” breaking down dead plant and animal material releasing nutrients into the ecosystem for recycling, and the pathogenic fungi are parasites responsible for 70% of all known plant diseases but nevertheless can be considered consumers of their living plant or animal hosts. Fungi also represent an important source of food for numerous animals which are the most important forest consumers-the mycophagists. These animals include invertebrates which predominantly browse on fungal hyphae, spores, ectomycorrhizal root tips and reproductive structures (fruiting bodies), and vertebrates, particularly mammals and less frequently birds, which eat fruiting bodies. Many mycophagous small mammals are in turn prey for raptors, mammalian carnivores, and martens and thus form important links in the trophic structure of forest ecosystems (Trappe et al. 2009). An example is the threatened northern spotted owl (Strix occidentalis caurina) that feeds primarily on northern ©ying squirrels (Glaucomys sabrinus) (Hallett et al. 2003), which in turn feed predominantly on hypogeous fungi (truf©es) (Hallett et al. 2003; Weigl 2007). Consequently factors that reduce truf©e production have a
detrimental effect on the population of northern ©ying squirrels and threaten the survival of the northern spotted owl.
